恒稳磁场效应对多元束配合物体系显色反应影响的研究(Ⅱ)

研究了恒稳磁场效应对W（V）－KSCN－RhB－PVA124体系显色反应的影响,发现在一定范围内,恒稳磁场能显著地提高该多元配合物体系显色反应的灵敏度．在0．05μg／mLW（V）0．7％KSCN,0．05％TiCl31．50mol／LHCl．0．12％PVA1240．0045％的RhB和室温条件下,强度为80mT的恒稳磁场能将最大吸收波长580nm处的显色灵敏度提高65．1％．     

Genomic instability in Gadd45a-deficient mice.

Gadd45a-null mice generated by gene targeting exhibited several of the phenotypes characteristic of p53-deficient mice, including genomic instability, increased radiation carcinogenesis and a low frequency of exencephaly. Genomic instability was exemplified by aneuploidy, chromosome aberrations, gene amplification and centrosome amplification, and was accompanied by abnormalities in mitosis, cytokinesis and growth control. Unequal segregation of chromosomes due to multiple spindle poles during mitosis occurred in several Gadd45a -/- cell lineages and may contribute to the aneuploidy. Our results indicate that Gadd45a is one component of the p53 pathway that contributes to the maintenance of genomic stability.     

高校综合信息统计管理系统

本文介绍了高校综合信息统计系统的设计思想和系统功能，阐明了该系统的特征．实际应用表明，该系统性能优良，具有应用推广价值．     

轨道空间上的运费不等式

研究了一类概率距离dp，它是全变差范数的自然推广．为方便运用这一抽象的距离，利用Wasserstein耦合方法，在Polish空间上用相对熵给出dp的上界．最后将这类距离推广到轨道空间上，建立了一类运费不等式．     

镁与间溴偶氮羧─m的β型显色反应研究

本文报道了镁与变色酸双偶氮衍生物的β型显色反应．并用分光光度法初步探讨了β型配合物的形成条件，实验结果表明，在弱酸性介质中，室温形成高灵敏的β型配合物，ε＝９．１１×１０￣４Ｌ·ｍｏＬ￣（－１）·ｃｍ￣（－１），但形成条件较为苛刻．     

非扩张映射的逼近不动点

对映射其中α１≥０，α０＞０，α１＞０，证明了当Ｔ是非扩张映射时，Ｓ在Ｂａｎａｃｈ空间中的毕卡迭代过程收敛到Ｔ的一个不动点．     

Physiology: does gut hormone PYY3-36 decrease food intake in rodents?

Batterham et al. report that the gut peptide hormone PYY3-36 decreases food intake and body-weight gain in rodents, a discovery that has been heralded as potentially offering a new therapy for obesity. However, we have been unable to replicate their results. Although the reasons for this discrepancy remain undetermined, an effective anti-obesity drug ultimately must produce its effects across a range of situations. The fact that the findings of Batterham et al. cannot easily be replicated calls into question the potential value of an anti-obesity approach that is based on administration of PYY3-36.     

New evidence on the earliest human presence at high northern latitudes in northeast Asia

The timing of early human dispersal to Asia is a central issue in the study of human evolution. Excavations in predominantly lacustrine sediments at Majuangou, Nihewan basin, north China, uncovered four layers of indisputable hominin stone tools. Here we report magnetostratigraphic results that constrain the age of the four artefact layers to an interval of nearly 340,000 yr between the Olduvai subchron and the Cobb Mountain event. The lowest layer, about 1.66 million years old (Myr), provides the oldest record of stone-tool processing of animal tissues in east Asia. The highest layer, at about 1.32 Myr, correlates with the stone tool layer at Xiaochangliang, previously considered the oldest archaeological site in this region. The findings at Majuangou indicate that the oldest known human presence in northeast Asia at 40 degrees N is only slightly younger than that in western Asia. This result implies that a long yet rapid migration from Africa, possibly initiated during a phase of warm climate, enabled early human populations to inhabit northern latitudes of east Asia over a prolonged period.     

求解非线性方程的两个有效算法

本文构造了求解非线性方程f(x)=0在区间[a,b]中单根的两种有效算法,给出了收敛性的证明.与Alefeld和Potra[1]的三种算法的收敛阶和效率指数相比,这两种新算法的收敛阶和效率指数更高.数值实验表明这两种新算法是可靠的,有效的.在函数值计算量意义下,特别是在算法终止条件tole(a,b)很小的情况下,对于某些问题,这两种新算法优于Alefeld和Potra的三种算法.     

Isolation,purification and characterization of a new organphosphorus hydrolase OPHC2

A bacterium with the capability of degrading organphosphorus, identified as Pseudomonas pseudoaicaligenes, is isolated from OP-treated soil. The organphosphorus hydrolase OPHC2 from this bacterium has been purified and characterized. OPHC2 has optimum activity for the reaction at 65℃ and pH 9.0 with methyl parathion as a substrate, it also shows good thermal and pH stability. Most metal ions and chemicals have no effect on the activity of OPHC2. The analyses of nucleotide sequence encoding OPHC2 and amino acid sequence of OPHC2 show that there are lower homologies with those of organphosphorus hydrolase reported in GenBank.